Specification :

VIAGRA® , an oral therapy for erectile dysfunction, is the citrate salt of sildenafil, a selective inhibitor of cyclic guanosine monophosphate ( cGMP) -specific phosphodiesterase type 5 ( PDE5) .

The physiologic mechanism of erection of the penis involves release of nitric oxide ( NO) in the
corpus cavernosum during sexual stimulation. NO then activates the enzyme guanylate cyclase,
which results in increased levels of cyclic guanosine monophosphate ( cGMP) , producing smooth
muscle relaxation in the corpus cavernosum and allowing inflow of blood.

02.00 USD per Tab/ pill through ordinary shipment , takes 10 days